function r2 = model_r2_mean_1D_v3(para,t,parameter)
% INPUTS:
% para(1): nu
% para(2): sigma^2
% t: time

N=(1:20000)';

if(size(t,1)==1)
    t = t';
end


freq = parameter(1);
A = parameter(2);
L = parameter(3);

c2 = para(1);
sigma2 = para(2)*para(1);